Piston-packing.



G R. 'I'HOIVIPSONu PISTON PACKING.

APPLIOATION FILED 11110.9. 190a.

92?,190, Patented July B 1909.

I i z" :Z! 20 -f I U22? Q Il e i 1 if WITNESSES MEMO eozyvfiljyzaflgoaoiz' ATTORNEYS v UNITED STATES PATENT oirrron.

GEORGE ROBERT THOMPSON, OF REPUBLIC, MICHIGAN, ASSIGNOR TO MARTHA THOMPSON,

OF REPUBLIG, MICHIGAN.

PISTON -PACKING.

Specification of Letters Patent.

Patented July 6, 1909.

-' Application filed December 9, 1908. Serial No. 466,674.

To all whomit may concern:

Be it known that I, GEORGE ROBERT THOMPSON, a citizen of the United States, and a resident of Republic, in the county of Marquette and State of Michigan, have invented a new and Improved Piston-Packing,

spread against the walls of the cylinder,

owing to its own normal resiliency.

The object of the invention is to provide a simple, inexpensive and durable piston packing ring, which consists of a tough, non-metallic and resilient substance, so that it is particularly well adapted for use in air compressors, air drill cylinders and the like,

.whi'ch, when it is accidentally broken into fragments, will not score or otherwise injure the interior of the cylinder if the piston continues to operate, which tends to revent leakage of air from one side of the plston to the other, and which even in small sizes can be easily sprung into place 11 on the piston. The invention consists in t e construction and combination of parts, to be more fully described hereinafter and particularly set forth in the claims.

Reference is to be had to the accompanyingdrawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views,

and in which- Figure 1 is a longitudinal section showing a part of a drill cylinder having a piston therein to which is applied an embodiment of my invention; Fig. 2 is a side elevation showing one form of the fiber ring; Fig. 3 is an enlarged plan view showing a part of a ring of modified form; and Fi .4 is a similar view, showing a part of a ring of still further modified form.

Before proceeding to a more planation of my invention, it should be clearly understood that the piston ring which I employ is fashioned from vulcanized or indurated fiber which is tough, non-metallic, and sufficiently resilient to permit its interior of the cylinder.

detailed ex-i being sprung even whenthe ring is of small diameter, upon the piston. It is thus adapted to replace cast-iron, for cast-iron rings of comparatively small diameter cannot be s rung into place without breaking them.

he fiber ring is thus articularly well adapted for use with the sma 1 diameter pistons of air drills and the like. The cast iron ring, moreover, has afurther disadvantage when used for drills and similar machines, owing to the fact that the shock of operation is apt to break it and the fragments, if the piston continues to operate, soon score and otherwise injure the The fiber ring requires no springs to spread it against the walls of the cylinder, as its natural resiliency is sufficient for this purpose. Needless to say, the fiber is of sufficient hardness to wear well in connection with air drills and the like.

Referring more particularly to the drawings, 10 represents the cylinder of an air drill having a piston 11 therein. The piston has annular grooves 12 adapted to receive the piston packing rings. One form of the fiber ring which I employ is shown in Fig. 2. The ring 13 has the inner periphery eccentric with the outer periphery, sothat the ring at one side is of greater thickness than atthe other. At the thinner side, the ring has a split 14 so that it can be spread and sprung into position within one of the grooves 12. The split 14 may be straight, or as shown in Fig; 4, may be'i'ormed by oppositely disposed tongues 15 at the ends of the split ring, which form a lap 'oint. The lap joint is efl'ectivein preventing leakage from one side of the piston to the other. j

Having thus described my invention, I

claim as new, and desire to secure, by Letters 

